Question

tìm x biết 

2 ( x + 10 ) + 20 = 100

Answer 1

2x + 20 + 20 = 100

2x + 40 = 100

2x = 100 - 40 = 60

x= 60: 2= 30

Answer 2

2 ( x + 10 ) + 20 = 100

2 ( x + 10 ) = 100 - 20

2 ( x + 10 ) = 80

( x + 10 ) = 80 : 2

x + 10 = 40

x = 40 - 10

x = 30

 Vậy x = 30

Answer 3

2 ( x + 10 ) + 20 = 100

2 ( x + 10 ) = 100 - 20

2 ( x + 10 ) = 80

( x + 10 ) = 80 : 2

x + 10 = 40

x = 40 - 10

x = 30

Answer 4

2 ( x + 10 ) + 20 = 100

2 ( x + 10 ) = 100 - 20

Ta có : 

2 ( x + 10 ) = 80

( x + 10 ) = 80 : 2

x + 10 = 40

x = 40 - 10

x = 30

 Vậy x = 30

Answer 5

2 ( x + 10 ) + 20 = 100

2 ( x + 10 ) = 100 - 20

2 ( x + 10 ) = 80

( x + 10 ) = 80 : 2

x + 10 = 40

x = 40 - 10

x = 30

 Vậy x = 30

Answer 6

2 ( x + 10 ) + 20 = 100

2 ( x + 10 ) = 100 - 20

Ta có : 

2 ( x + 10 ) = 80

( x + 10 ) = 80 : 2

x + 10 = 40

x = 40 - 10

x = 30

 Vậy x = 30

Answer 7

2 ( x + 10 ) + 20 = 100

2 ( x + 10 ) = 100 - 20

2 ( x + 10 ) = 80

( x + 10 ) = 80 : 2

x + 10 = 40

x = 40 - 10

x = 30

 Vậy x = 30